And a southwest employee knew it and made good on a promise. Here is ABC's Steve osunsami. Reporter: We've all been there. You land safely but your bag doesn't. They said oh it'd be coming on your later original flight and we'll call you when it arrives at 6:30. Reporter: It happened to Stacey hurt in Pittsburgh. She arrived home, but her bag with important medicine she depends on in her fight with colon cancer was still stuck in Nashville. I immediately got very distraught, very emotional because I knew I had chemo therapy the next morning. Reporter: By the time her bags arrived in the wee hours of the morning, the delivery services had all gone home. And that's where this agent at southwest airlines went above and beyond. Sarah Rowan had promised that the bag would be delivered, so she first wrote a note she put inside the bag: "Sorry for the delay." "Kick that cancer's butt." And then, at 3:00 A.M., she personally drove it to the passenger's home. And put it on the front porch. This was the moment when Stacey hurt came back to the airport to thank and meet her new friend. Sometimes it's the small things that make the biggest difference. Steve osunsami, ABC news, Atlanta. Thank you for watching tonight. I'll see you back here tomorrow night. Have a great evening.

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